Star boxer Ryan Garcia tested positive for the performance-enhancing substance ostarine the day before and the day of his upset win over Devin Haney last month, per a Voluntary Anti-Doping Association letter sent to all parties Wednesday and obtained by ESPN.
The urine samples were collected prior to the fight, but the results weren't known until later.
Garcia has 10 days to request that his B-sample be tested. Garcia's A-sample also screened positive for 19-norandrosterone, but its presence is unconfirmed until further lab analysis.
"Everybody knows that I don't cheat," Garcia said in a video posted on X. "Never taken a steroid. ... I don't even know where to get steroids. ... I barely take supplements. Big lies, I beat his ass."
Oscar De La Hoya's Golden Boy Promotions said in a statement that it is working with Garcia's team to "determine how this finding came to be."
"Ryan has put out multiple statements denying knowingly using any banned substances -- and we believe him," Golden Boy said in its statement.
Garcia, 25, floored Haney three times and won by majority decision, but that result now stands to be overturned unless the B-sample returns negative, which is rare.
"We learned about this situation not too long ago and it's unfortunate Ryan cheated and disrespected both the fans and the sport of boxing by fighting dirty and breaking positive not once, but twice," Haney said in a statement to ESPN.
"... Ryan owes the fans an apology, and by his recent tweet he still thinks this is a joke. We put our lives on the line to entertain people for a living. You don't play boxing. This puts the fight in a completely different light. Despite the disadvantage, I still fought on my shield and got back up! People die in this sport. This isn't a joking matter."
Garcia (25-1, 20 KOs) also missed weight ahead of the fight, registering 143.2 pounds for the WBC 140-pound title fight. Garcia paid Haney (31-1, 15 KOs) upward of $600,000 for his failure to make weight. It also meant Garcia was ineligible to win the title, though he rose to No. 2 in ESPN's junior welterweight rankings following the major upset.
Haney, who fights out of Las Vegas, remained the junior welterweight champion even in defeat. He fell to No. 4 in ESPN's 140-pound rankings and lost his pound-for-pound recognition after being ranked No. 6 by ESPN going into the fight.
"Safety, fairness, and integrity in professional athletic competition are essential," the New York State Athletic Commission said in a statement to ESPN. "The Commission is in communication with VADA and is reviewing the matter."
Ostarine is a selective androgen receptor modulator that attaches to proteins in the body and effectively tells muscles to grow. It is used to aid performance by helping athletes build muscle mass and enhance their rate of fat loss and also to increase stamina and recovery ability.
It has been on the World Anti-Doping Agency's banned list since 2008 and in 2022 was listed as an anabolic agent by WADA.
Ostarine has been used in boxing before. Lucian Bute tested positive for it in 2016 following a draw with Badou Jack in their WBC super middleweight title fight. The result was changed to a DQ win for Jack.
Amir Khan was handed a two-year ban by UK Anti-Doping (UKAD) after he tested positive for ostarine following his sixth-round TKO loss to Kell Brook in 2022.
Haney was a -900 favorite, according to ESPN BET, but he closed at -575 after Garcia missed weight. The slick-boxing Haney, the former undisputed lightweight champion, had never been knocked down entering the fight, but Garcia deposited him on the canvas in Rounds 7, 10 and 11 with his lightning-quick left hook to pull out the victory.
The win was a career-altering performance for Garcia, who has never won a world title but boasts a massive social media presence with more than 12 million followers on Instagram. His lone career defeat came via seventh-round TKO vs. Gervonta Davis last April.
Haney defeated future Hall of Famer Vasiliy Lomachenko last May to retain his four 135-pound titles. He made his 140-pound debut in December with a shutout decision victory over Regis Prograis to win the WBC junior welterweight title.